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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Scientific skepticism is healthy. Scientists should always challenge themselves to improve their understanding. Yet this isn't what happens with climate change denial. Skeptics vigorously criticise any evidence that supports man-made global warming and yet embrace any argument, op-ed, blog or study that purports to refute global warming. This website gets skeptical about global warming skepticism. Do their arguments have any scientific basis? What does the peer reviewed scientific literature say?

Posted on 19 November 2018 by Guest Author

When do 97% of people agree on anything, even ice cream? In scientific circles, consensus is a rare trophy, held to famously exacting standards. When a scientific consensus is finally reached — e.g., the Earth orbits the sun; water freezes at 32°F, 0°C; blood is red — a new fact joins the foundations of human discovery.

Under normal circumstances, a 97% consensus of the world’s leading scientists on anything would establish it as fact and compel action if needed. But our circumstances are not normal. Only 12% of Americans realize that that the scientific consensus on climate change is greater than 90%. Even among people who are Alarmed or Concerned about climate change, the consensus is somewhat unknown. Of the Alarmed, 84% understand the scientific consensus on climate change (16% do not); and 73% of the Concerned (27%).

This is a great opportunity for climate communicators.

Background:

In 2004, Naomi Oreskes published The Scientific Consensus on Climate Change, in which she established the substantive “scientific consensus on the reality of anthropogenic climate change.” The paper was widely cited, including in the Academy-award winning movie An Inconvenient Truth.

Posted on 18 November 2018 by John Hartz

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Scientists acknowledge key errors in study of how fast the oceans are warming

A major study claimed the oceans were warming much faster than previously thought. But researchers now say they can’t necessarily make that claim.

The sun sets over sea ice floating on the Victoria Strait along the Northwest Passage in the Canadian Arctic Archipelago during the summer of 2017. (AP Photo/David Goldman)

Scientists behind a major study that claimed the Earth’s oceans are warming faster than previously thought now say their work contained inadvertent errors that made their conclusions seem more certain than they actually are.

Two weeks after the high-profile study was published in the journal Nature, its authors have submitted corrections to the publication. The Scripps Institution of Oceanography, home to several of the researchers involved, also noted the problems in the scientists' work and corrected a news release on its website, which previously had asserted that the study detailed how the Earth’s oceans “have absorbed 60 percent more heat than previously thought.”

“Unfortunately, we made mistakes here,” said Ralph Keeling, a climate scientist at Scripps, who was a co-author of the study. “I think the main lesson is that you work as fast as you can to fix mistakes when you find them.”

Editor's Pick

Ranking of countries’ goals shows even EU on course for more than double safe level of warming

Vendors near a state-owned coal-fired power plant in China. Photograph: Kevin Frayer/Getty Images

China, Russia and Canada’s current climate policies would drive the world above a catastrophic 5C of warming by the end of the century, according to a study that ranks the climate goals of different countries.

The US and Australia are only slightly behind with both pushing the global temperature rise dangerously over 4C above pre-industrial levels says the paper, while even the EU, which is usually seen as a climate leader, is on course to more than double the 1.5C that scientists say is a moderately safe level of heating.

The aim of the paper is to inform climate negotiators as they begin a two-year process of ratcheting up climate commitments, which currently fall far short of the 1.5-to-2C goal set in France three years ago.

The related website also serves as a guide to how nations are sharing the burden of responding to the greatest environmental threat humankind has ever faced.

Posted on 14 November 2018 by dana1981

Now designated as California’s deadliest fire, the still-raging Camp Fire by November 13 had led to 42 deaths, with many residents still unaccounted for and more than 7,000 structures destroyed. (Image credit: NASA)

The reality is that about 57 percent of the state’s forests are owned and managed by the federal government, and another 40 percent by families, companies, and Native American tribes. Forest management does play some role in creating wildfire fuel, but some wildfires aren’t even located in forests. Moreover, scientific evidence clearly shows that climate change is exacerbating California’s wildfires in different ways:

The warming atmosphere is slowing the jet stream, leading to more California heat waves and high-pressure ridges in the Pacific. Those ridges deflect from the state some storms that would otherwise bring much-needed moisture to slow the spread of fires.

Posted on 13 November 2018 by Guest Author

Don’t feed the trolls. You’ve heard this advice before, but how can anyone sit on their hands when the trolls are just so … wrong? When you encounter a rude and inaccurate comment, often the best bet is to ignore it altogether. But if you’re feeling inspired, you can look beyond the toxicity and aim for a productive outcome. The thing you ought not do, however, is take the bait and lock horns with the offender. That’s a certain path to a lose-lose situation.

What would you do if confronted with this comment?

The High Priest of Environmental Causes Al Gore was out promoting his waste of cellulose In January, 2006 – when promoting his Oscar-winning (yes, Oscar-winning) documentary, An Inconvenient Truth – Gore declared that unless we took “drastic measures” to reduce greenhouse gasses, the world would reach a “point of no return” in a mere ten years. He called it a “true planetary emergency.” Well, the ten years passed today, we’re still here, and the climate activists have postponed the apocalypse. Again.

Tracing the spread of the myth

This gem appeared among a volley of comments on the Facebook page of a science advocacy organization. But the text was not the work of the commenter.

Posted on 12 November 2018 by dana1981

Over the past two years, the Trump administration, aided by the Republican-controlled Congress, has eroded the Obama administration’s policy efforts to curb global warming. Climate activists had hoped to reverse some of those losses in this year’s midterm elections, but the results were a mixed bag. Here is the rundown of where we stand.

What can House Democrats do with the majority?

The Democrats won control of the House of Representatives and will hold about 232 seats (53 percent) starting in 2019. This gives them control over legislation in that chamber of Congress. Democrats will become House committee chairs, who choose the bills that receive a hearing and a vote in a given committee. Democrats will also be able to choose the Speaker of the House – likely to be Nancy Pelosi – who decides what bills come to the floor for a vote after they’ve passed out of committees.

We’re thus in a similar scenario as in 2009, when House Democrats led by Nancy Pelosi passed the American Clean Energy and Security Act carbon cap and trade bill. At that time, Democrats had a majority in the Senate, but not a 60-vote supermajority. Because the bill lacked the votes to defeat a Republican filibuster, it was never brought to the Senate floor for a vote. Republicans now hold the Senate and White House, so climate legislation has no chance of passing until either Democrats take control of those branches (and overcome a Senate filibuster), or a significant number of Republican lawmakers stop denying the need to address the existential threat posed by climate change.

In the meantime, Democrats can now play a major role in setting the federal budget, which means they can protect funding for climate science research and for federal agencies like the EPA. So, we can at least keep learning about the dangers posed by climate change as the Trump administration tries to increase the carbon pollution that’s creating those threats. The House Science Committee will now be controlled by Democrats rather than some of Congress’ worst science-denying Republicans like Lamar Smith (retired) and Dana Rohrabacher (defeated), and thus will thankfully no longer hold theatrical hearings to deny basic climate science.

Posted on 11 November 2018 by John Hartz

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Sighting of sperm whales in Arctic a sign of changing ecosystem, say scientists

Rare sighting in the Canadian Arctic as a growing number of species expand their range into warming waters

Sperm whales were spotted in the Canadian Arctic. Photograph: SeaTops/Getty Images

A rare sighting of sperm whales in the Canadian Arctic is the latest sign of a quickly changing ecosystem, say scientists, as a growing number of species expand their range into warming Arctic waters.

Brandon Laforest, a marine biologist with the World Wildlife Fund, and guide Titus Allooloo were working on a project monitoring the effect of marine traffic on the region’s narwhal population when they spotted the pair of large whales just outside Pond Inlet, a community at the northern tip of Baffin Island in September.

Video of the incident, released at the end of October, captures the second known sighting of sperm whales in the region. In 2014, hunters from Pond Inlet spotted them in the area.

At first, Allooloo and Laforest thought the dark shapes in the water were killer whales – another species that has become a frequent visitor to the waters as temperatures creep up. But the distinct shape of the dorsal fin surprised Allooloo – a veteran hunter.

“They’re not known by us, we don’t know too much about them,” Allooloo told the CBC.

Posted on 7 November 2018 by Guest Author

When you don’t like the message, attack the messenger. It’s an age-old tactic and an easy way to energize opposition while distracting from the real issue at hand.

With climate change, ad-hominem attacks on scientists are intended to shake public trust in the scientific evidence that underpin the whole issue. After all, who could be more villainous than the world’s climate scientists? Does one really think this group of bicycle-riding, organic-cotton-wearing PhDs might be pulling off a skillfully-coordinated global conspiracy, one involving 100 years of research from hundreds of scientists all over the world?

The notion of scientists-as-conspiracists seems preposterous – but for those who have never met a practicing scientist, are unfamiliar with the scientific process, and are emotionally invested in the idea that humans aren’t changing the climate, maybe it does seem plausible that climate scientists are stealthily, greedily, falsifying their reports to score the next big grant.

Ergo, this common complaint from those alleging climate scientists are “in it for the money”:

Most climate science is being paid for to prove a hypothesis, not disprove it. Scientists are getting funding to prove a result based on a single variable. And, guess what? Of course they’re going to prove it to keep getting paid. Scientists are told, “Take a million bucks, and prove global warming is a result of manmade CO2.” That’s what’s happening in climate science, and it’s not the way science is supposed to work.

This is a modified version of a comment on a science news Facebook page.

Such sentiments are reliable laugh lines at professional scientific conferences, but given how pervasive they are, they’re not funny at all. Nonetheless, they can spur some good questions. How do research grants work? Why won’t this myth die? And where’s the real financial lever in the climate change debate?

Read on to see how three experts in science and communication unpack this misconception and clear the air.

The video opens with Patrick Brown of the Carnegie Institute for Science, Stanford University, explaining that ECS is the measure of the amount of global warming expected from a doubling of the carbon dioxide levels from pre-industrial times. Penn State’s Michael Mann says that doubling could come as early as mid-century, and he says a 3-degree C increase in warming is generally considered to be in the mid-range of estimates.

But Mann points to lots of uncertainty over that 3-degree figure and says some project the increase may be “as little as” two degrees C and others lean toward an increase of 4.5 to 5 degrees C.

Pointing to research he conducted with scientist Ken Caldeira of Stanford, Brown says that the models best simulating the recent past “tend to produce more warming” than those low- or mid-range estimates. He says their research “cuts off the probability of these low estimates of warming” and instead indicates higher-end estimates “appear to be more likely.”

Posted on 5 November 2018 by Guest Author

Posted on 4 November 2018 by John Hartz

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Startling new research finds large buildup of heat in the oceans, suggesting a faster rate of global warming

A post-sunset swimmer at Moonlight Beach in Encinitas, Calif., this month. (Mike Blake/Reuters)

The world’s oceans have been soaking up far more excess heat in recent decades than scientists realized, suggesting that Earth could be set to warm even faster than predicted in the years ahead, according to new research published Wednesday.

Over the past quarter-century, Earth’s oceans have retained 60 percent more heat each year than scientists previously had thought, said Laure Resplandy, a geoscientist at Princeton University who led the startling study published Wednesday in the journal Nature. The difference represents an enormous amount of additional energy, originating from the sun and trapped by Earth’s atmosphere — the yearly amount representing more than eight times the world’s annual energy consumption.

In the scientific realm, the new findings help resolve long-running doubts about the rate of the warming of the oceans before 2007, when reliable measurements from devices called “Argo floats” were put to use worldwide. Before that, differing types of temperature records — and an overall lack of them — contributed to murkiness about how quickly the oceans were heating up.

The higher-than-expected amount of heat in the oceans means more heat is being retained within Earth’s climate system each year, rather than escaping into space. In essence, more heat in the oceans signals that global warming is more advanced than scientists thought.

Posted on 3 November 2018 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook Page during the past week from Sunday through noon on Friday.

Editor's Pick

Earth’s carbon dioxide levels are likely the highest they've been in 15 million years

Earth’s average global temperature from 2013 to 2017, as compared to a baseline average from 1951 to 1980.

We’ve entered some profoundly unfamiliar planetary territory.

Amid a backdrop of U.S. politicians still questioning whether the changing climate is attributable to humans (it is), it's quite likely that we’ve actually boosted Earth's carbon dioxide — a potent greenhouse gas — to the highest levels they’ve been in some 15 million years.

The number 15 million is dramatically higher than a statistic frequently cited by geologists and climate scientists: That today's carbon levels are the highest they've been on Earth in at least 800,000 years — as there's irrefutable proof trapped in the planet's ancient ice.

Though scientists emphasize that air bubbles preserved in ice are the gold carbon standard, there are less direct, though still quite reliable means to gauge Earth's long-ago carbon dioxide levels. These measurements, broadly called proxies, include the chemical make-up of long-dead plankton and the evidence stored in the breathing cells, or stomata, of ancient plants.

Scientists have identified this 15 million number by measuring and re-measuring proxies all over the world.

Posted on 1 November 2018 by Guest Author

Carbon brief has a very nice interactive report that show the impacts of climate change at 1.5C, 2C and beyond. It presents the various projected climatic, ecological, and economic changes on both global and regional scales. It is an impressive dive into the relevant literature.

On Twitter, Doug McNeall said something I’ve often wondered myself. Essentially, why don’t projections of large climatic and ecological changes lead to large projected economic damages? Of course, I don’t know the economic literature particularly well, so one potential answer is that some economic analyses do project large changes. However, it also seems that some certainly do not.

One possibility is that the global economic impact will indeed be relatively small, even if the climatic and ecological changes are large. Of course, even if this were the case, this wouldn’t necessarily imply that a cost-benefit analysis wouldn’t still suggest that it would be beneficial to address climate change.

Additionally, even if the global economic impact is relatively small, that doesn’t mean that there can’t be large impacts in some regions, or that some of the impacts (such as the loss of ecosystems, for example) aren’t things that are difficult to quantify economically, at least in a way that we would all broadly agree with.

However, I do think there are reasons to be cautious about some of these economic analyses. Let me provide a caveat up front. I’m not an expert at this, so am happy to be corrected if I get something wrong, and am partly writing this in the hope that I might learn something more.

For starters, these analyses are typically linear. This essentially means that they can say nothing about the possibility of some kind of large shock. Some of these analyses actually suggest the possibility of quite small global economic impacts even for extremely large changes in climate (see links below), which would seem to suggest that there is some point at which these calculations break down.

Posted on 31 October 2018 by Riduna

China is the world’s largest emitter of greenhouse gasses so we should be particularly interested in the level of its emissions, as well as the success of the practices and policies it pursues to reduce them. After all, China’s emissions are likely to have the greatest influence on future global warming and our ability to keep average global temperature rise to less than 2°C above those of the pre-industrial era.

However, CO2 emissions in 2017 for China are not known with any accuracy, even by the Chinese government. Some estimates suggest 9.8 gigatonnes (Gt.), while others claim it to be 11.7 Gt. Clearly both can not be right and it is possible that both estimates could be wrong.

CFC-11 Emissions

The 1987 Montreal Protocolhas been signed by China and 197 other countries. The Protocol commits all countries to abolish production and use of ozone depleting halocarbon gasses to zero by 2010 because they destroy the ozone layer which protects the earths surface from harmful ultra violet radiation. Halocarbons are also very powerful greenhouse gasses, particularly CFC-11 which has a lifetime in the atmosphere of 45 yearsor more

The Kigali Amendment(2016) further requires phase-down of all hydrofluorocarbon gasses which have a greenhouse effect, some of which can be used as a substitute for halocarbons.

If all countries had complied with the Montreal Protocol, it should have been expected that global CFC-11 emissions would have fallen sharply after 1995 when developed countries were required to reduce their production and use and to zero by 2010 when all other countries ceased production. However, as show in Fig. 1, this is not what has happened.

On the basis of air samples taken in South Korea, NOAA’s Dr Montzka concluded that the likely source of CFC-11 emissions was in east Asia, even though all countries in that region reported to the UN administering authority that they remained in compliance with the Montreal Protocol.

Posted on 30 October 2018 by dana1981

The Guardian editors recently decided to discontinue their Science and Environment blog networks. This is the story of Climate Consensus - the 97%.

Way back in 2012, newspapers were struggling to hang on to readers. Blogs were all the rage, and with the stability of the Obama administration, a steadily improving economy, the UK still in the EU (how I long for those good old days), there wasn't today's demand for daily newspapers. Papers were trying to come up with new ideas, and the Guardian editors decided to experiment with international blog networks.

It was a very clever idea. There were lots of smart science and environment bloggers out there, writing on their own blogs for free. By folding them into The Guardian, the paper was able to add their expert analysis. By splitting the ad revenue, they guaranteed some profit for the paper while bringing in new readers for the expert analysis, and the bloggers who previously wrote for free got a bit of pay for their work, plus the prestige of affiliation with The Guardian. It was a win-win.

Posted on 29 October 2018 by dana1981

Note: this will be our final entry on Climate Consensus - the 97%. The Guardian has decided to discontinue its Science and Environment blogging networks. We would like to thank this great paper for hosting us over the past five years, and to our readers for making it a worthwhile and rewarding endeavor.

The federal carbon pollution price will start low at $20 per ton in 2019, rising at $10 per ton per year until reaching $50 per ton in 2022. The carbon tax will stay at that level unless the legislation is revisited and revised.

Paris was a key motivator behind the Canadian carbon tax

The Preamble in the Act is worth reading. It begins by noting “there is broad scientific consensus that anthropogenic greenhouse gas emissions contribute to global climate change” (this is somewhat understated – carbon pollution is the dominant factor). It also notes that Canada is already feeling the impacts of climate change through factors like “coastal erosion, thawing permafrost, increases in heat waves, droughts and flooding, and related risks to critical infrastructures and food security.”

The Preamble also notes that in 1992, Canada signed the UNFCCC whose objectives include “the stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system,” and that Canada ratified the Paris Agreement, whose aims include limiting global warming to less than 2°C above pre-industrial temperatures.

Canada’s Paris commitment requires cutting its carbon pollution by 30% below 2005 levels by 2030. Prior to the implementation of the carbon tax, its policies were rated Highly Insufficient to meet that goal. Instead Canada’s emissions were on track to fall only about 4% below 2005 levels by 2030. So, the carbon tax is an important policy to close that gap.